Android

package com.ishidakorea.test02

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import java.lang.Exception

class MainActivity : AppCompatActivity(), A.interA, Child.interChild
{
    override fun Child_EventFire()
    {
        // Child Class Listener
    }
    override fun A_SendPost()
    {
        // AA Class Listener
    }

    override fun onCreate(savedInstanceState: Bundle?)
    {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        var A1 = A()

    }


}

class A : Child(), Child.interChild {

    interface interA
    {
        fun A_SendPost()
    }

    lateinit var LinstenerA : A.interA

    init {
        LinstenerA = this@A as A.interA // Exception
    }

    fun FireA()
    {
        if (LinstenerA != null)
            LinstenerA.A_SendPost()
    }
    
    override fun Child_EventFire()
    {

    }

    
}

open class Child {

    interface interChild
    {
        fun Child_EventFire()
    }

    lateinit var LinstenerB : interChild

    init {
            LinstenerB = this@Child as interChild // OK
    }

    fun Fire()
    {
        if (LinstenerB != null)
            LinstenerB.Child_EventFire()
    }



}

An error occurs while creating a new listener from a parent class that inherits a child class that has a listener.

Why is that?

If you know anyone, please advise.

Hi,
In Android Studion ,<pre>why the methods are crossed out here ?
because when I insert AsyncTask the methods don't work

package com.example.entertainmentlab.ui.store;
    
    import android.os.Bundle;
    import android.view.LayoutInflater;
    import android.view.View;
    import android.view.ViewGroup;
    import android.widget.ImageView;
    import android.widget.TextView;
    import android.widget.Toast;
    
    import androidx.annotation.NonNull;
    import androidx.annotation.Nullable;
    import androidx.fragment.app.Fragment;
    import androidx.fragment.app.FragmentManager;
    import androidx.fragment.app.FragmentTransaction;
    import androidx.lifecycle.Observer;
    import androidx.lifecycle.ViewModelProviders;
    
    import com.example.entertainmentlab.R;
    import com.example.entertainmentlab.ui.setting.SettingViewModel;
    
    public class StoreFragment extends Fragment {
    
        private StoreViewModel StoreViewModel;
    
        public View onCreateView(@NonNull LayoutInflater inflater,
                                 ViewGroup container, Bundle savedInstanceState) {
            StoreViewModel =
                    ViewModelProviders.of(this).get(StoreViewModel.class);
            View root = inflater.inflate(R.layout.fragment_store, container, false);
           final ImageView MusicButton = root.findViewById(R.id.music_btn);
    
    
    
    
    
    
    
            MusicButton.setOnClickListener(new View.OnClickListener() {
               @Override
               public void onClick(View v) {
                   try {
    
                       Fragment fragment = new BlankFragment();
                       FragmentManager fragmentManager = getActivity().getSupportFragmentManager();
                       FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
                       fragmentTransaction.replace(R.id.nav_host_fragment_container, fragment);
                       fragmentTransaction.addToBackStack(null);
                       fragmentTransaction.commit();
                   }catch (Exception e ){
                       Toast.makeText(getActivity(), "erro  "+e, Toast.LENGTH_SHORT).show();
                   }
               }
           });
    //        StoreViewModel.getText().observe(getViewLifecycleOwner(), new Observer<String>() {
    //            @Override
    //            public void onChanged(@Nullable String s) {
    //                textView.setText(s);
    //            }
    //        });
            return root;

public static string RestUrl = DeviceInfo.Platform ==
    DevicePlatform.Android ?
        "http://10.0.2.2:44300/api/todoitems/{0}" :
        "http://localhost:44300/api/todoitems/{0}";

public async Task> RefreshDataAsync()
{
    Items = new List();

    Uri uri = new Uri(string.Format(Constants.RestUrl, string.Empty));
    try
    {
        HttpResponseMessage response = await client.GetAsync(uri);
        if (response.IsSuccessStatusCode)
        {
            string content = await response.Content.ReadAsStringAsync();
            Items = JsonConvert.DeserializeObject>(content);
        }
    }
    catch (Exception ex)
    {
        Debug.WriteLine(@"\tERROR {0}", ex.Message);
    }

    return Items;
}

{Java.Net.SocketException: Connection reset
  at Java.Interop.JniEnvironment+InstanceMethods.CallIntMethod (Java.Interop.JniObjectReference instance, Java.Interop.JniMethodInfo method, Java.Interop.JniArgumentValue* args) [0x0006e] in :0 
  at Java.Interop.JniPeerMembers+JniInstanceMethods.InvokeVirtualInt32Method (System.String encodedMember, Java.Interop.IJavaPeerable self, Java.Interop.JniArgumentValue* parameters) [0x0002a] in :0 
  at Java.Net.HttpURLConnection.get_ResponseCode () [0x0000a] in :0 
  at Xamarin.Android.Net.AndroidClientHandler+<>c__DisplayClass46_0.b__2 () [0x00000] in :0 
  at System.Threading.Tasks.Task`1[TResult].InnerInvoke () [0x0000f] in /Users/builder/jenkins/workspace/archive-mono/2020-02/android/release/external/corert/src/System.Private.CoreLib/src/System/Threading/Tasks/Future.cs:534 
  at System.Threading.Tasks.Task.Execute () [0x00000] in /Users/builder/jenkins/workspace/archive-mono/2020-02/android/release/external/corert/src/System.Private.CoreLib/src/System/Threading/Tasks/Task.cs:2319 
--- End of stack trace from previous location where exception was thrown ---

  at Xamarin.Android.Net.AndroidClientHandler.DoProcessRequest (System.Net.Http.HttpRequestMessage request, Java.Net.URL javaUrl, Java.Net.HttpURLConnection httpConnection, System.Threading.CancellationToken cancellationToken, Xamarin.Android.Net.AndroidClientHandler+RequestRedirectionState redirectState) [0x00372] in :0 
  at Xamarin.Android.Net.AndroidClientHandler.SendAsync (System.Net.Http.HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) [0x002d0] in :0 
  at System.Net.Http.HttpClient.FinishSendAsyncBuffered (System.Threading.Tasks.Task`1[TResult] sendTask, System.Net.Http.HttpRequestMessage request, System.Threading.CancellationTokenSource cts, System.Boolean disposeCts) [0x0017e] in /Users/builder/jenkins/workspace/archive-mono/2020-02/android/release/external/corefx/src/System.Net.Http/src/System/Net/Http/HttpClient.cs:506 
  at TodoREST.RestService.RefreshDataAsync () [0x0006b] in C:\Projects\SandBox\Xamarin\Mirosoft Examples\Web Services\ToDoREST\TodoREST\Data\RestService.cs:30 
  --- End of managed Java.Net.SocketException stack trace ---
java.net.SocketException: Connection reset
    at java.net.SocketInputStream.read(SocketInputStream.java:209)
    at java.net.SocketInputStream.read(SocketInputStream.java:139)
    at com.android.okhttp.okio.Okio$2.read(Okio.java:136)
    at com.android.okhttp.okio.AsyncTimeout$2.read(AsyncTimeout.java:211)
    at com.android.okhttp.okio.RealBufferedSource.indexOf(RealBufferedSource.java:306)
    at com.android.okhttp.okio.RealBufferedSource.indexOf(RealBufferedSource.java:300)
    at com.android.okhttp.okio.RealBufferedSource.readUtf8LineStrict(RealBufferedSource.java:196)
    at com.android.okhttp.internal.http.Http1xStream.readResponse(Http1xStream.java:186)
    at com.android.okhttp.internal.http.Http1xStream.readResponseHeaders(Http1xStream.java:127)
    at com.android.okhttp.internal.http.HttpEngine.readNetworkResponse(HttpEngine.java:737)
    at com.android.okhttp.internal.http.HttpEngine.readResponse(HttpEngine.java:609)
    at com.android.okhttp.internal.huc.HttpURLConnectionImpl.execute(HttpURLConnectionImpl.java:471)
    at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:407)
    at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getResponseCode(HttpURLConnectionImpl.java:538)
}